By April 1975, a Communist group known as the Khmer Rouge, led by Pol Pot, seized control of Cambodia, renaming the country Democratic Kampuchea. Civil war had existed in Cambodia since 1970. Between 1970 and 1973, during the Vietnam War, the United States bombed much of the countryside of Cambodia and manipulated Cambodian politics to support the rise of pro-West Lon Nol as the leader of Cambodia. The Khmer Rouge used the United States’ actions to recruit followers and as an excuse for the brutal policies they exercised when in power. The Khmer Rouge’s polices were guided by its belief that the citizens of Cambodia had been tainted by exposure to outside ideas, especially by the capitalist West. The Khmer Rouge persecuted the educated — such as doctors, lawyers, and current or former military and police. Christian, Buddhist and Muslim citizens also were specifically targeted. In an effort to create a society without competition, in which people worked for the common good, the Khmer Rouge placed people in collective living arrangements — or communes — and enacted “re-education” programs to encourage the commune lifestyle. People were divided into categories that reflected the trust that the Khmer Rouge had for them; the most trustworthy were called “old citizens.” The pro-West and city dwellers began as “new citizens” and could move up to “deportees,” then “candidates” and finally “full rights citizens”; however, most citizens never moved up. Those who refused re-education were killed in the fields surrounding the commune or at the infamous prison camp Tuol Sleng Centre, known as S-21. Over four years, the Khmer Rouge killed more than 1.7 million people through work, starvation and torture.

The Khmer Rouge was removed from power when communist Vietnam invaded in January 1979 and established a pro-Vietnamese regime in Cambodia. Many survivors fled to refugee camps in Thailand; of these, many went on to immigrate to the United States.

Despite the heavy casualties and injustices inflicted specifically on the Cambodian Muslim population — the Cham — many genocide scholars believe the events in Cambodia do not qualify as genocide under the United Nations Convention because intent to destroy one specific ethnic or religious group cannot be proven. Instead, many genocide scholars call these events an “auto-genocide” because it occurred across all of society instead of targeting one group.

More than 20 years later, the Extraordinary Chambers in the Courts of Cambodia (ECCC) is bringing the former leaders of the Khmer Rouge to trial for their crimes against humanity. On June 26, 2010, the ECCC found Kaing Guek Eav, alias Duch, guilty of crimes against humanity and grave breaches of the Geneva Conventions of 1949, sentencing him to 35 years in prison. Kaing Guek Eav, a Khmer Rouge deputy and chairman of S-21, is the first of four former leaders charged to stand trial before the ECCC.